> Since trade is conducted largely in USD, that means other governments must purchase USD to trade. This is the core of trade deficits. Foreign countries buy US dollars so they can trade with other people. That guarantees the deficit since they give us something in exchange for USD

I'm not convinced it works like that. When a foreign country buys something from another foreign country using USD, the seller country then receives that USD. The seller country then use those dollars do buy something else from a third country - unless they have imbalanced trade and keep accumulating the dollars, like China does. But, in general case, there's only a need for a limited number of USD in circulation to serve as "working capital" for all foreign exchange. There's no need to keep getting new dollars, as the old ones get recirculated.